Process for operating a measurement device of the vibration type

Measurement device of the vibration type comprising:

• at least one exciter arrangement for generating an adjustable excitation frequency ω;
• at least one vibration-capable part for containing a measurement medium, wherein the exciter arrangement and the vibration-capable part are configured such that a time-dependent force f(t)=F sin(ωt)+g(t) with at least one sinusoidal component having a force amplitude F, the adjustable frequency ω, and with a possible extraneous time varying force factor g(t), which is driven by the exciter arrangement, acts upon the at least one vibration-capable part;
• and
• a sensor for measuring a response signal of the vibration-capable part to determine a phase shift Ψ between the response signal and a signal component of the force f which oscillates with the frequency ω, the measurement device being configured such that the phase shift Ψ is input to a frequency controller of the exciter arrangement so that the excitation frequency ω will be automatically adjusted as a function of Ψ.

Process for operating a measurement device of the vibration type, comprising:

• exciting at least one vibration-capable part of a measurement device to vibration according to an adjustable excitation frequency ω by applying a time-dependent force f(t)=F sin(ωt)+g(t) with at least one sinusoidal component having a force amplitude ω, the adjustable excitation frequency w, and with a possible extraneous time varying force factor g(t), to the at least one vibration-capable part;
• determining, by the measurement device, a measurement quantity of a measurement medium of the vibration-capable part by measuring a response signal of the vibration-capable part;
• determining a phase shift Ψ between the response signal and a signal component of the force f which oscillates with a frequency ω;
• and
• adjusting the frequency ω as a function of the phase shift Ψ.